The present invention relates to hydraulic systems and pertains particularly to a hydraulic system for excavator mounted dynamic rock breakers.
The circuit of the present invention is devised particularly for use in hydraulic excavator mouted rock breakers such as those disclosed in U.S. Pat. No. 3,915,501. The rock breaker, as disclosed in the aforementioned patent, includes an impact-driven ripper tip mounted on the outer end of the boom of the excavator for breaking rock, concrete and the like. The mounting of the breaker on the excavator facilitates the manipulation of the breaker to positions normally hard to reach. The rock breaker system is driven by a hydraulic motor with hydraulic fluid supplied by the system of the hydraulic excavator itself.
One convenient source of pressure for operation of the rock breaker element is the swing circuit of the excavator. The swing circuit is that circuit which rotates the platform of the excavator. Since that circuit is not normally in operation or required at the same time that the rock breaker is in operation, the fluid thereof may conveniently be supplied to operate the rock breaker itself. In such a system, however, it is desirable that proper priority be maintained between the swing motor of the vehicle and the breaker motor. Accordingly, the present invention is devised to meet these requirements.